macosx: fix lion fullscreen button in dark ui in some cases

Especially this is needed when fullscreen is true in video prefs, but video has not started yet.

modules/gui/macosx/MainWindowTitle.m

@@ -174,7 +174,17 @@
     else if (sender == o_green_btn)
         [[self window] performZoom: sender];
     else if (sender == o_fullscreen_btn)
-        [[VLCCoreInteraction sharedInstance] toggleFullscreen];
+    {
+        // set fs directly to true, as the vars can be already true in some configs
+        var_SetBool( pl_Get( VLCIntf ), "fullscreen", true );
+
+        vout_thread_t *p_vout = getVout();
+        if( p_vout )
+        {
+            var_SetBool( p_vout, "fullscreen", true );
+            vlc_object_release( p_vout );
+        }    
+    }
     else
         msg_Err( VLCIntf, "unknown button action sender" );